Just bought a 2000 Explorer XLT in great condition, it came with a harness for trailer lights, but it does not have a hitch, just a ball on the bumper. The person I bought it from said that it plugs in somewhere under the vehicle by the spare tire as the vehicle was already pre-wired for trailer lights even though it did not have a towing package. I have looked everywhere and cannot find where it plugs into, can someone please help? Thanks for your time.